Cortical Layer 5b pyr. cell with [Na+]i mechanisms, from Hay et al 2011 (Zylbertal et al 2017)

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Accession:230326
" ... Based on a large body of experimental recordings from both the soma and dendrites of L5b pyramidal cells in adult rats, we characterized key features of the somatic and dendritic firing and quantified their statistics. We used these features to constrain the density of a set of ion channels over the soma and dendritic surface via multi-objective optimization with an evolutionary algorithm, thus generating a set of detailed conductance-based models that faithfully replicate the back-propagating action potential activated Ca(2+) spike firing and the perisomatic firing response to current steps, as well as the experimental variability of the properties. Furthermore, we show a useful way to analyze model parameters with our sets of models, which enabled us to identify some of the mechanisms responsible for the dynamic properties of L5b pyramidal cells as well as mechanisms that are sensitive to morphological changes. ..."
Reference:
1 . Hay E, Hill S, Schürmann F, Markram H, Segev I (2011) Models of neocortical layer 5b pyramidal cells capturing a wide range of dendritic and perisomatic active properties. PLoS Comput Biol 7:e1002107 [PubMed]
2 . Zylbertal A, Yarom Y, Wagner S (2017) The Slow Dynamics of Intracellular Sodium Concentration Increase the Time Window of Neuronal Integration: A Simulation Study Front. Comput. Neurosci. 11(85):1-16 [PubMed]
Citations  Citation Browser
Model Information (Click on a link to find other models with that property)
Model Type: Neuron or other electrically excitable cell;
Brain Region(s)/Organism: Neocortex;
Cell Type(s): Neocortex L5/6 pyramidal GLU cell;
Channel(s): Na/Ca exchanger; Na/K pump; I Sodium;
Gap Junctions:
Receptor(s):
Gene(s):
Transmitter(s):
Simulation Environment: NEURON;
Model Concept(s): Dendritic Action Potentials; Detailed Neuronal Models; Action Potentials; Reaction-diffusion; Synaptic Plasticity; Active Dendrites; Olfaction;
Implementer(s): Zylbertal, Asaph [asaph.zylbertal at mail.huji.ac.il];
Search NeuronDB for information about:  Neocortex L5/6 pyramidal GLU cell; I Sodium; Na/Ca exchanger; Na/K pump;
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L5PC_converted
mod
Ca_HVA.mod
Ca_LVAst.mod
cadp.mod
CaDynamics_E2.mod *
Ih.mod *
Im.mod *
K_Pst.mod *
K_Tst.mod *
nadp.mod
Nap_Et2.mod *
naSyn.mod
NaTa_t.mod *
NaTs2_t.mod *
ncx.mod
SK_E2.mod *
SKv3_1.mod *
                            
TITLE sodium calcium exchange
: taken from Courtemanche et al Am J Physiol 1998 275:H301

NEURON {
	SUFFIX ncx
	THREADSAFE
	USEION ca READ cao, cai WRITE ica
	USEION na READ nao, nai
	RANGE ica, itot, imax, rate
	GLOBAL kna, kca, gamma, cont_factor, ksat, naf, is_fixed
    NONSPECIFIC_CURRENT i_na
    NONSPECIFIC_CURRENT icont : remove electrogenic effect
}

UNITS {
	(mA) = (milliamp)
	(mV) = (millivolt)
	F = (faraday) (coulombs)
	R 	= (k-mole)	(joule/degC)
}

PARAMETER {
	imax	= 3.2       (mA/cm2)
	kna	=  87.5     (mM)
	kca	=  1.38     (mM)
	gamma	= .35		: voltage dependence factor
    cont_factor = -1    (1)
    ksat = 0.1          (1)
    naf = 15.0      (mM)
    is_fixed = 0        (1)
}

ASSIGNED {
	celsius	(degC)
	v	(mV)
	ica	(mA/cm2)
	i_na	(mA/cm2)
	itot	(mA/cm2)
    icont   (mA/cm2)
    rate    (mA/cm2)
	cao	(mM)
    cai	(mM)
	nao	(mM)
	nai	(mM)
}

BREAKPOINT {
	:LOCAL rate
    if (is_fixed==0) {
        rate = pumprate(v,nai,nao,cai,cao)
    }
    if (is_fixed==1) {
        rate = pumprate(v,naf,nao,cai,cao)
    }
	i_na =  3*rate
	ica = -2*rate
	itot=i_na+ica
    icont=itot*cont_factor
}

FUNCTION pumprate(v,nai,nao,cai,cao) {
	LOCAL q10, Kqa, KB, k
	k = R*(celsius + 273.14)/(F*1e-3)
	q10 = 3^((celsius - 37)/10 (degC))
	Kqa = exp(gamma*v/k)
	KB = exp( (gamma - 1)*v/k)
	pumprate = q10*imax*(Kqa*nai*nai*nai*cao-KB*nao*nao*nao*cai)/((kna*kna*kna + nao*nao*nao)*(kca + cao)*(1 + ksat*KB))
}